问题
Recently, i tried to include open source package (iperf3) to target image via Yocto build. (Updating local.conf for IMAGE_INSTALL += "iperf3" , as the project already corresponding recipe). But the final image did not include in root file system. I tried the same by adding to package group recipe in /recipe-core/packagegroups/RDEPENDS_packagegroup* and was able to include it successfully.
Can someone provide me explanation for the behavior.
回答1:
When you write IMAGE_INSTALL += "iperf3" in your local.conf, that will immediately add iperf3 to IMAGE_INSTALL. If your image adds the base rootfs by doing IMAGE_INSTALL ?= "....", then that default value will never be added, as IMAGE_INSTALL already have a value.
If you want to modify IMAGE_INSTALL from local.conf (and a lot other variables), you should always do that with a delayed append / prepend. I.e.
IMAGE_INSTALL_append = " iperf3"
Note the leading space.
来源：https://stackoverflow.com/questions/46333278/yocto-difference-between-core-image-extra-install-and-image-install